Firefox flaws make up 44% of all browser bugs?
10 Nov 2009 @ 15.11

Firefox flaws accounted for nearly half (44 per cent) of all browser bugs in the first half of 2009 - according to a survey which fails to factor in the seriousness of browser flaws.

A study by web application security firm Cenzic makes a decent fist of providing an overview of server-side web, but blots its copy-book with a brief foray into commenting on browser bugs. Of the browser vulnerabilities mapped by Cenzic, Firefox racked up 44 per cent of the total, with Safari bugs making up a 35 per cent slice of the browser vulnerabilities. Internet Explorer was third, with 15 per cent, with Opera copping for six per cent.

Cenzic's one-paragraph treatment of browser security suggests the number of Safari bugs was mainly due to vulnerabilities reported in iPhone Safari, and not much else. In particular, Cenzic fails to mention that the seriousness of flaws and the availability of exploits has a big bearing on how comparatively safe a browser choice might turn out to be.

The majority of media reports on Cenzic's survey fail to make the point that counting vulnerabilities alone is a bit pointless.

"For a proper and fair comparison one needs to dig a lot deeper than just looking at the numbers," Thomas Kristensen, CTO on web security notification firm Secunia, told El Reg.

"Other factors need to be taken into account for a proper comparison; this includes the type of vulnerabilities and thus the underlying type of coding errors, the impact of the vulnerabilities, the time it takes the vendor to fix the reported vulnerabilities, how easy it is to update the software thus how quickly the users (learn about and is able to) apply the patches.

"One may also want to look at the general design of the product, the efforts invested in improving the code and conducting internal security reviews and quality assurance, the usability with regards to certain security related features, the handling of plug-ins (how easy is it to lure the user into installing untrusted plug-ins) and so on," Kristensen concludes.

The release of Cenzic's report coincided with Firefox's fifth anniversary on Monday, though this is probably a slightly unfortunate coincidence. The vast majority of the 29-page study concentrates on server-side flaws, drawing on data from enterprise use of Cenzic's managed security assessment services and work by its security researchers.
This section of the report (pdf) is far more detailed.

Of 3100 reported vulnerabilities, an increase of over ten per cent, more than three in four (78 per cent) involved web vulnerabilities. Many web applications continue to be vulnerable to information leaks, cross site scripting (XSS), authentication flaws and session management problems. Flaws in commercial applications, SQL Injection, and XSS dominated the threat landscape surveyed by Cenzic.